Data transmission apparatus for controlling contention between data transmissions of a plurality of types of applications by setting transmission internal according to each application bandwidth requirement

Abstract

A data transmission apparatus in which the bandwidth necessary for an application is determined and is communicated to a transmission interval counting function. The transmission interval counting function determines a transmission interval according to the necessary bandwidth and effects transmit control on a transmission unit transmitting function with timing set at this transmission interval so as to transfer data in a desired bandwidth. Owing to the above construction, even when a plurality of types of applications for transmitting data at desired times exist and they perform data transmissions while sharing the use of a network, the contention between the data transmissions in the network can be prevented from occurring. This prevents data losses and delays in data transmission from increasing.

What is claimed is: 
     
       1. A data transmission apparatus comprising: identifying means for identifying an identifier of an application in a receiving side of a data transmission;   storing means for storing the identifier of the application and a transmission bandwidth necessary for the application in relation to each other;   transmission bandwidth extracting means for extracting the transmission bandwidth which is stored in said storing means and which corresponds to the identifier of the application identified by said identifying means;   sending interval determining means for determining a sending interval for transmitting a unit of data in accordance with the transmission bandwidth extracted by said transmission bandwidth extracting means; and   data transmitting means for transmitting the unit of data in accordance with the sending interval determined by said sending interval determining means.   
     
     
       2. The data transmission apparatus according to claim 1, wherein the identifier of the application identified by said identifying means is an identifier of a protocol, and the transmission bandwidth necessary for the application is determined depending on a type of the protocol. 
     
     
       3. The data transmission apparatus according to claim 1, wherein the identifier of the application identified by said identifying means is input by a user, and the transmission bandwidth necessary for the application stored in said storing means is input by the user. 
     
     
       4. The data transmission apparatus according to claim 1, wherein the transmission bandwidth necessary for the application is determined in accordance with a throughput of the application. 
     
     
       5. The data transmission apparatus according to claim 1, wherein the identifier of the application identified by said identifying means is identified in accordance with a connection, and the transmission bandwidth necessary for the application is determined in accordance with the connection. 
     
     
       6. A data transmission method which stores in advance an identifier of an application and a necessary transmission bandwidth for the application in relation to each other, said data transmission method comprising: determining the identifier of the application in a receiving side of a data transmission;   extracting the necessary transmission bandwidth corresponding to the identifier of the application;   determining a sending interval for a data transmission unit in accordance with the necessary transmission bandwidth; and   transmitting the data transmission unit in accordance with the determined sending interval.   
     
     
       7. The method of claim 6, wherein the identifier of the application identifies a protocol for the application and the necessary transmission bandwidth is determined based on the identified protocol. 
     
     
       8. The method of claim 6, further comprising: receiving the identifier of the application as input from a user; and   receiving the necessary transmission bandwidth as input from a user.   
     
     
       9. The method of claim 6, wherein the identifier of the application and the necessary transmission bandwidth are determined in accordance with a connection. 
     
     
       10. A data transmission apparatus comprising: a transmitter; and   a necessary transmission bandwidth determination device that sends necessary bandwidth information corresponding to an identifier of an application in a receiving side of a data transmission to the transmitter, wherein the transmitter receives transmission data and divides the transmission data into plurality of transmission units corresponding to the identifier of the application determines transmission intervals for transmitting the transmission units based on the sent necessary transmission bandwidth information and transmits the transmission units in accordance with the determined transmission intervals.   
     
     
       11. The data transmission apparatus of claim 10, wherein the transmission data is received from at least one application and the necessary bandwidth determination device determines the necessary bandwidth information based on at least one of a type of protocol used by the at least one application, an input to the at least one application from a user, and a throughput of the at least one application. 
     
     
       12. The data transmission apparatus of claim 10, wherein the transmission units are of a fixed length. 
     
     
       13. The data transmission apparatus of claim 12, wherein the transmission interval is determined using the equation:   m=(p/B)-(p/Rmax)     where m is the transmission interval, p is the length of the transmission unit, B is the necessary bandwidth, and Rmax is the maximum bandwidth of a transmitting medium being used to transmit the transmission data.   
     
     
       14. The data transmission apparatus of claim 10, wherein the necessary bandwidth determination device further comprises a required bandwidth table storage device that stores a required bandwidth table that identifies a correspondence between a type of protocol of the at least one application and a required bandwidth. 
     
     
       15. The data transmission apparatus of claim 10, wherein the transmission units are of an arbitrary length. 
     
     
       16. The data transmission apparatus of claim 15, wherein the transmitter further comprises: a transmission interval counter;   a transmission unit length counter; and   a transmission unit transmitter.   
     
     
       17. The data transmission apparatus of claim 16, wherein the transmission unit transmitter transmits a transmission unit when a start signal is received from the transmission interval counter, the transmission unit length counter begins counting a data transmission unit length when the start signal is received from the transmission interval counter, and the transmission unit length counter reports the transmission unit length back to the transmission interval counter when a transmission end signal is received from the transmission unit transmitter. 
     
     
       18. The data transmission apparatus of claim 17, wherein the transmission interval is determined based on the transmission unit length received from the transmission unit length counter and wherein the transmission interval counter sends the start signal to the transmission unit transmitter once the transmission interval has expired. 
     
     
       19. The data transmission apparatus of claim 10, wherein the necessary bandwidth information is determined based on a connection number of the transmission data. 
     
     
       20. The data transmission apparatus of claim 19, wherein the connection number is one of a port number, an IP address, and a Virtual Path Identification/Virtual Channel Identification.